Please note that old diffiety site is available at diffiety.ac.ru. Very old diffiety school site (school.diffiety.org) is available here. More recent information about diffiety schools can be found here. For the latest school see “Most Recent School”

This site facilitates communication of Diffety research group. The aim

is to discuss various Diffiety-related concepts in blogs and comments, develop lecture notes interactively and publish more robust material in pdf/tex form. For technical details see FAQ/HowTo section. The site

concept of the solution space of a given system of (non-linear) PDEs – much like an algebraic variety does with respect to solutions of a given system of algebraic equations.

For a good demo of site abilities please, see Presentation by Maria Sorokina. The thing is that the page text contains usual TeX formulas in dollars which are nicely rendered to the user. Comments may contain formulas as well, so it’s easy to discuss mathematics on this site.